Iatrogenic risk and anatomical variability of the posterior tibial nerve bifurcation relative to the Dellon-McKinnon line: Assessing safety in medial ankle procedures.

BACKGROUND

Precise knowledge of the posterior tibial nerve (PTN) branching pattern is critical to avoid iatrogenic injury during medial foot and ankle procedures. This study aimed to perform a morphometric assessment of the PTN terminal branching in relation to the Dellon-McKinnon Line (DML) to identify safe surgical zones.

METHODS

Forty-three formalin-fixed adult cadaveric limbs were dissected. The bifurcation points of the PTN, its level and distance were measured relative to the DML. Bifurcation angle, and foot length were also measured. Statistical analysis of the measured parameters was performed.

RESULTS

The PTN bifurcated above the level, at the level and below the level of DML in 53.5%, 37.2% and 9.3% of specimens. The mean bifurcation angle was 16.92°.

CONCLUSION

These findings provide quantitative boundaries for establishing safe surgical corridors in medial ankle ORIF (open reduction and internal fixation), ligamentous reconstruction, and tarsal tunnel decompression.